Typewriting machine



Patenten .am 17, 1924.

iran eras TENT oFFicl-z.

LOUIS T. REICHERS, F ARLINGTON, NEW JERSEY, ASSIGNOB- TO UNDEBWOOD LYZPIE- WRITER COMPANY, OF NEW YORK, N. Y., A CORPORATION 0F DMIAW rrrnwnrrme MACHINE Application led Hay 8,

To all whom. it may concern.'

Be it known that I, Louis T. RmcHERs, a citizen of the United States, residing in Arlington, in the county of Hudson and State of New Jerse have .invented certain new and useful m rovements in Typewriting Machines, of w ich the following isv a specification.

This invention relates to means for rel'ducing the noise produced by .-the striking of types against the platen of a typewriting machine.

An object of the invention is to produce a front-strike action of simple and inexpensive construction without departing to any great extent 4from the general construction of type-actions heretofore employed.

The invention resides in improved means for stopping the movement of the typebar just as the type reaches the printing position, and may comprise an extensible and collapsible device, such as a pair of pivotally joined links forming a toggle, one of these links being pivoted to the typecarrying arm of the type-bar, and the other link belng pivotally connected to the upstanding arm of a bell-crank lever which is actuated by a key-lever, the bell-crank lever being connected independently of the toggle-links to the type-bar for actuating the latter, the toggle-links being of such length that when. stretched from a collapsed to an extended position they will be Aeffective to stop the movement of the type just as it reaches the printing position. A

feature of the invention is the emplo ent' of a spring to prevent the toggle-lin s be-` comingflocked on dead center.

Other features and advantages will here` inafter appear.

In the accompanying drawings,

Figure 1 is a side elevation with parts in section, and shows two type-actions embodying the present invention, in une of which the parts are in the normal position, and in the other of `which the parts are in the operated position, with the type at4 the printing point on the platen.

Figure 2 is a partial front elevation showing the arcuate arrangement of the type bars in the type segment, and means, forming a feature of the present invention, for guiding the upstanding arms of the bellcrank levers to prevent the pull of the move- 1922. Serial No. 559,127.

ment-limitin toggle-links from defiecting these, arms o the bell-crank levers laterally.

In the embodiment of the invention shown in the drawings, for each of the type-actions a type-key 1 is carried by the forward end of a depressible key-lever y2, pivoted at its rear end on a rod 3, and the key-lever 2 is raised from depressed to normal positionv by a compressible restoring spring 4. The key-lever. 2 carries a stud 5 engaging in a curved slot 6 in the end of a short normally upwardly-inclined front arm 7 of a bellqcrank lever ivoted upon a transverse rod 8, the slot 6 eing curved upwardly towards its open end to produce an easier initial key-actiomtogether with accelerated movement of the bell-crank lever, this slot beingv onl the whole substantially radial to the pivot point 8 of the bell-crank lever. The bell-crank. lever has a long upstanding arm 9, the up er end ofy which is pivoted at 10 to the fiirward end of a bent link l1, which at its rear end curves upwardly and is pivotally connected at 12 to a normally rearwardly and slightly downwardly extending short arm 13 of an upwardly and rearwardly swinging type-bar having a long and normally forwardly-extending arm 14 carrying a typehead 15 having types 16 to print upon the yfront of a platen 17. All the type-bars are pivoted, by means of pivot-holes therethrough, on an arcuate fulcrnm-orming wire 18 carried by a type-bar segment 19 provided with slots 20 for guiding the typebars. The long upstanding lever-arms 9 of the bell-crank levers become longer and longer towards the sides of the machine and are bent inward more and more at 2 1, so that the upper inwardly-bent ends 22 of these lever-arms are radial to the arcuate type-bar segment 19, to correspondv with the arcuate arrangement of the type-bars, as is commonly the'case in front-strike typewriting machines. v

When a type-key 1 is struck and depressed by the finger of the typist, the connections from the key-lever to the type-bar, comprising the bell-crank having the lever-arms 7 and 9, and the link 11, swing the type-carrying ,arm 14 ofthe type-bar from its normally substantially horizontal position, occupied in one of the type-actions shown in Figure 1, rearwardly to the printing position of the types 16, as is shown in the other type-action illustrated in Figure l. rlhe construction and arrangement of the lever and link mechanism is such thatl the movetion to normal position, this return movement being assisted by the weight of the type-bar and its type-head 15. The typeaction, as so far described, does not greatly' differ from type-actions which have been heretofore employed. i

Before proceeding further, it should be noted that the type-action as so far described, is entirely edective for typing operations, and` in this respect, may be considered a complete type-action. However, it is to be noted that the acquired momentum of the moving parts of the type-action, and particularly of the long lever-arm 14 of the type-bar and especially of the type-head 15, the impact of which is utilized to cause the types 16 to print, will produce a comaratively loud clacking noise, due to the hammer-like blow received by the platen 17 and this noise is objectionable, especially in view of the high speed at which the machine is usually operated.

According to thev present invention, positively-acting means are provided for checking or stopping the further movement of the type-bar, type-head 15 and types 16 carried' therebyv just about at the position or just preceding the position reached at which a type 16 will come in contact with the printing surface of the platen 17, in the absence of a work-sheet thereon, so that when a work-sheet (not shown) is in place upon the platen the work-sheet and usual ink-ribbon (not shown) will receive the printing impact of a type 16, the hammer-like blow of the types 16 being expended upon the work-sheet and not being to any extent communic'ated to the platen upon which the work-sheet is held at the typing position.

In the particular embodiment of the invention shown in the drawings, such means comprise a pair of toggle-links 23 and 24 pivoted together at 25, the other end of the upper toggle-link 23 being pivoted at 26 to the type-carrying arm 14 of the type-bar at a point comparatively near to the type-head 15 and considerably nearer to the type-head than to the pivot point 18 of the type-bar,

'and the other end of the lower toggle-link 24 bein pivoted to the' upstanding arm 9 of the ell-crank lever at the upper end thereof at the pivot point 10 for the typereeaeoa actuating link 11. lin the normal position of the several parts of the type action, the toggle-links 23 and 24 are in collapsed condition and are folded near to each other with the lower toggle-link 24 extending substantially horizontally rearward from its pivot point 10 on the upstanding arm 9 of the bell-crank lever, as is .shown by one of the type-actions illustrated in Figure 1. When a type-key 1 is depressed to swlng the long type-carrying arm 14 of the type-bar upwardly and rearwardly, by means of the operating connections hereinbefore "described, including the bell-crank lever and link 11, the upward and rearward movenient of the type-carrying type-bar arm 14 together with the forward and slightly downward movement of the pivot point 10 on the upstanding bell-crank arm 9, will enpand or straighten out the toggle-joint formed by the pivotally connected togglelinks 23, 24, as is shown by the other typeaction illustrated in Figure 1. The togglelinks 23 and 24 are` of the proper length so as to become fully expanded or straightened into alignment with each other just at the moment of time and just at the position reached in the typing movement of the types 16 at which one of Athese types, de-

pending upon the case-shift position of the` to produce printing pressure of the type,

and that the typing movement of the type will be arrested in time to prevent a noiseproducing hammer blow being delivered to the printlng surface of the platen, this blow being received by the interposed worksheet, and the printing surface of the platen receiving only the pressure caused by the printing upon the work-sheet. After the printing of one of the types 16 upon the work-sheet, further rearward movement of the type-carrying type-bar arm 14, and consequently of the types 16, is positively prevented by the straightened or stretched togglo-links 23 and 24, which operate to lock the type-action as soon as printing has been llO eiected, so as to prevent further rearward that is, forwardly instead of backwardly and downwardly, a spring 27 is provided to initiate the correct or rearward and downward folding` movement of the togglelinks 23 and 24. The spring 27is shown as a bowed or substantially U-shaped retractile spring which may be formed of suitable spring wire, and is shown as bowed or bent at its middle towards the pivot ,point 26 of the upper toggle-link 23, and at one of its ends is pivotallyv connected at 28 to the type-carrying type-bar arm 14, and at its other end is pivotally connected at 29 to the upper toggle-link 23. so that the spring 27 will be effective -to break the lock of the toggle-links in their aligned or stretched condition shown in Figure 1, to permit free return movement of the type-bar, and the spring`27 also will assist in such return movement.

ln order to prevent the springing or lateral deflection of, the upstanding lever arms v9 of the bell-crank levers due to their angular pull upon the straightened togglelinks 23 and 24, particularly at the sides of the machine, an arcuate guide-bar 30,V provided in its forward edge with rearwardlyextending vertical guide-slots 31, to receive the upstanding bell-crank arms 9, is mounted on Athe machine below and to the front of the type-bar segment 19, as shown in the drawings, in such position that the bell-crank arms 9 will engage in the guideslots 31 just below the lateral bend 21 therein.

An inspection of the drawings, in connection with the foregoing description, will make it clear that the movement limiting device for the type-carrying arm 14 of the type-bar, comprising the toggle-links 23 and 24, plays no part whatever in swinging the type-bar to the typing position, that is to say, these links do not communicate any movement from the bell-crank lever to the type-bar; nor, on the other hand, do these toggle-links hamper or interfere with the swinging movement of the type-bar as the type-bar swings to the printing point. However, these links do positively limit or prevent any further movement of the typebar after printing has been eected. 1n

this connection, 'it is to be further noted.

that the toggle-links 23 and 24 form a con- /tinuous or unbroken connection to the typecarrying arm of the type-bar for positively limiting the throw of the type-bar, the typebar not being permitted to strike against anything, the movement of the 4 type-bar being stopped by the stretching of the pivoted links 23 and 24' into alignment,' at which point, of course, the limit of eXtension is reached, and the rearwardly-swinging type-bar is thus ybrought to a stop noiselessly. The final result is that the momentum of the swinging type-bar and typehead 15 carried thereby 'is left free to be y limprovements may be used without others.

Having thus described my invention, 1 claim;

1. A noise-reducing type-action for typewriting machines, comprising, in combination with a platen, a swinging type-ban' means including a type-key for swinging the type-bar to printing, position, said means including apart of the'type-'action which l has a receding movement from the normal position of the type-bar as the type-bar recedes from its normal position and swings to-printing position, and means to prevent further' movement of the type-bar after.

printing has been effected, comprising an,

extensible and collapsible device connected to the type-bar and to said receding part of the type-action, further movement of the type-barafter printing being prevented b v reason of the oppositely-moving type-bar and said recedin part of the type-action causing said devlce to reach its limit of extension.

2. A noise-reducing type-action for typewriting machines, comprising, in combination with a platen, a swinging type-bar, means including a type-key for swinging the type-bar to printing position, said means includingy a part of the type-action which has a receding movement from the normal position of the type-bar as the typebar recedes from its normal position and swings to printing position, and means to prevent further movement of the type-bar after printing has been effected, comp .ising a plurality of pivotally-joined links pivotally connected to the type-bar and to said receding part of the type-action, said links being of such length as to be fully extended bythe oppositely moving type-barand said receding part of the type-action when the type 'on the ,type-bar has reached the printing position.

3. A noise-reducing type-action for typewriting machines, comprising, in combination with a platen, a swinging type-bar, means including a type-key for Swingin the type-bar to printing position, said means including a part of the type-action which has a receding movement from the normal position of the type-bar asthe typebar recedes from its normal position and swings to printing position, and means to' prevent further movement of the type-bar when printing by the type has taken place. comprising a pair of toggle links, one of which is directly pivotally connected to the aft type-carrying arm of the type-har and the other of which is directly pivotally connected. to said receding part of the typeaction, said links being of such length as to be fully .straightened with their three pivot-points in line in the printing position of the type carried by the type-bar.

4. A noise-reducing type-action for a front-strike typewriting machine, comprising, in combination with a platen, a pivoted type-bar having a long rearwardly-swinging type-carrying arm, and having at the other s1 e of its pivot a short actuating arm, a bell-crank-lever pivoted below and forwardly of the pivot of the type-bar, and having a long upstanding arm and a short front arm, a link pivotally connecting the long upstanding arm of the bell-crank-lever to the short actuating arm of the type-bar, a depressible key-lever for actuating the latter to swing the type-bar to printing position, and means for preventing movement of the type beyond the printing position thereof,

` comprising a pair of toggle-links, one of which is vpivotally connected to the ty ecarrying arm of the type-bar, and the ot er of which is pivotally connected to the upstanding arm of the bell-crank-lever, said toggle-lmksbeing of such length as to be straightened into alignment in the printing position of the type.

5. A noise-reducing type-action for a front-strikeA typewriting machine, comprising, in combination with a platen, a pivoted type-bar having a long rearwardly-swinging type-carrying arm, and havingat the other side of its pivot a short actuating arm, a bell-crank-lever pivoted below and forwardly of the pivot of the type-har, and having a long upstanding arm and a short front arm, a link for actuating the type-bar pivotally connecting the long upstanding arm of the bell-crank-lever to the short actuating arm of the type-bar,`a depressible key-lever connected to the short front arm of the hellcrank-lever, for actuating the latter to swing the type-bar to printing position, and means for preventing movement of the type beyond the printing position thereof, comprising a `pair of toggle-links, one of which is pivotally connected to the type-carrying arm of the type-bar, and the other of which is pivotally connected to the upstandin arm of the bell-crank-lever at the same point thereon at which said link for actuating the typebar is connected, said toggle-links being effective to stop the movement of the type-bar and type by reason of reaching the limit of their extensibility.

6. A noise-reducing type-action for a front-strike 'typewritin machine, comprising, in combination wit a platen, a pivoted type-bar having a long rearwardly-swinging type-carrying arm, and having at the other side oit its pivot a short actuating arm, a

aerea/ica p hell-cra t -lever pivoted helow and forwardly of the pivot of the type-har, and having a l arm and a short `iront arm,

long upstanding a link pivotal y connecting the long upstanding arm of 4.the bell-crank-lever to the short actuatin arm of the type-bar, a depressihle keyever connected to the short front arm of the bell-crank-lever, for actuating the latter to swing the type-bar to printing position, means for preventing movement of the type beyond the printing position thereof, comprising a pair of togglelinks, one of which is pivotally connected to the type-carrying arm of the type-har, and the other of which is pivotally connected to the upstandin arm of the bell-crank-lever, said toggle-1in is being of such len. h as to be straightened into alignment in t e printing posltion of the type, and a s 'ring tending to collapse the toggle-links ownvvardly away from dead center as the type-har 'returns from the printing position to normal position. f'

7. A noise-reducing type-action ,'Or a front-strike typewriting machine, comprising, in combination 'with a platen, a pivoted type-bar having a long rearwardly-swinging type-carrying arm, and having at the ot er side of its pivot a short actuating arm, a `loell-crank-lever pivoted below and forwardly of the pivot of .the type-bar, and having a long upstanding arm and a short front arm, a link for actuating the type-bar pivotally connecting the long upstanding arm of the bell-crank-lever to the short actuating arm of the type-bar, -a depressible key-leverconnected to the short front arm of the bell-crank-lever, for actuating the latter to swing the type-bar to printing osition, means for preventing movement o the type 'heyond the printing position thereof,

vcomprising a pair of toggle-links, one of which is pivotally connected to the typeearrying arm ofthe type-bar, and the other 'of which is pivotally connected to the upstanding arm of the bell-crank-lever at the point thereon at which said link for actuating the type-bar is connected, and a retractile spring connected to the type-carrying arm of the type-bar and to the adjacent toggle-link for moving said toggle-links downwardly away from their dead center as the type-har returns from the printing position to its normal position, and for overcoming the tendency of the links to overthrow at the toggle joint when the links are moved to their extended position.

8. ln a front-strike typewriting machine, the combination with a system of typeactions comprising swinging type-hars pivoted on the machine in an arc, key-levers, and type-bar-actuatin'g connections between the key-levers and the type-bars, said connections including levers having upstanding lever-arms connected to the type-hars, of an lOO extensible` and collapsible device for each type-action connected to said upstanding arm and to the type-carrying arm of thetype-bar for limiting the throw of the latter in its typing movement, and guiding means for said upstanding lever-arms to prevent them from being deflected laterallfy by reason of the angular pull thereon o s ald device.

9. In a front-strike typewriting machine, tne combination with a system of type-actions comprising swinging type-bars pivoted on the machine in an arc, bell-crank levers pivoted in horizontal alignment `below `and forwardly of the type-bar pivots and having upstanding lever-arms, key-levers connected to the bell-crank-levers to swing the ilpstanding lever-arms forwardly when the key-levers are depressed, and links connecting the upstanding lever-arms of the bellcrank-levers to the type-bars lto actuate'the latter, of an extensible' and collapsible device for each type-action comprising links l connected to the upstanding lever-arm of the bell-crank-lever and to the type-carrying arm of the type-bar for limiting the throw of the type-bar in its typing movement, and means to prevent the angular pull of said devices from laterally deecting the upstanding lever arms of the bell-crank levers comprising an arcuate guide-plate having therein guide-slots for the upstanding leverarms of the bell-crank levers.

10. A type-action for a front-strike typewriting machine, comprising a swinging type-bar, a key-lever, connecting means between the key-lever and the type-bar to actuate the latter, includin a stud on the keylever, and further inclu ing a lever having an arm provided with a curved slot in which the stud works, said slot beingV curved in such manner as gradually to accelerate the movement communicated by the key-lever to said slotted lever, the slotted lever thereby correspondingly accelerating the movement of the type-bar as ity swings the type to the printing point, and means for limiting the throw of the type-carrying arm of the typebar as it swings to the printing position comprising an extensible and collapsible device connected to the type-carrying arm of the type-bar and to a movable part of said connecting means relatively to which said arm has a receding movement as it swings to the typing position.

ll. A type-action for a front-strike typewriting machine, comprising a swin ing type-bar, a bell-crank lever having a ong arm connected to the type-bar to swing the latter to the typing position and having a short arm provided with a curved substantially radial slot, a key-lever, a stud on the 'key-lever projecting into said slot, said slot being so curved as to impart a graduallyincreasing accelerated movement to the belll crank-lever for correspondingly accelerating the type-carryingarm of the type-bar and to, said upstanding arm of the bellcranklever.

l2. ln a noise-reducing type-action for a typewriting machine, in combination, a type-action including a pivoted type-bar arm, and means for limiting the printing stroke 'of said arm, comprising pivotally connected links with the extremities pivoted to'said type-bar arm adjacent its free ena and to another moving part of ythe typeaction; 'said links, `during the printing stroke, being extended to the limit, and thereafter being effective to stop the movement ofsaid arm.

13. lin a noise-reducing type-action for a typewriting machine, in combination,y a type-action includin a pivoted vtype-bar arm, means lfor limitmg'the printing stroke of said arm, comprising pivotally connected links with the extremities pivoted to said type-bar arm adjacent its free end and to another moving part of the type-action; said links, during the printing strike, being extended to the limit, and ythereafter being eective to stop the movement of said arm, and spring means connected between the type-bar arm and its adjoining link to overcome the tendency of the links to overthrow at the joint when the same are moved to the extended, position, and also to e'ect breakage of the toggle joint when the links have reached dead center for assisting`the return movement of. said type-bar arm.

la. lin a typewriting machine, in combination, a platen, a pivoted arm carrying a type-bar to coact with the platen, a keylever to actua-te the type-bar, an operative connection between said arm and said keylever for imparting movement to the latter from the former to eEect printing, and toggle-links pivoted to said bar and tov a movable part of said operative means and extended to limit the printing stroke it Said arm independently of said platen.

15, lin a typewriting machine, in combination, a platen, a pivted-arm carrying a' lever for imparting movement to the latter from the former to e'ect printing, togglelinks pivoted to said bar and to a movable part of said operative means and extended to limit the printing stroke of said arm' independently of said platen, and springmeans mounted between the type-bar arm and one of said links to preventA the overthrow thereot at the pivoted joint and to impart initial return movement to said arm after thel printing stroke.

16. A. noise-reducing typewriting machine, comprising, in combination with a platen, a type-action including a pivoted arm carrying a type-bar, a link pivoted to said arm adjacent its free end, and a'link' pivoted to another moving part of the type-action, said links pivoted together as a toggle and when extended arresting the printing stroke movement of the type-bar to prevent a,

noise-producing hammer blow being de-v livered to the printing surface of the platen, and means carried between the type-bar arm and one of said links to prevent overthrow of the toggle joint.

17. A noise-reducing type-action for a ront-strike typewriting machine, in combination with a platen, an arm carrying a Leeaeoa type-bar and pivotally mounted therebelow for rearward swinging from a normallydisposed substantially horizontal position to a relatively vertical position for eHecting,`

printing at the platen, operating means, in-

cluding a key-lever, to swinglsaid arm, and toggle-links pivoted to said arm and to a movable part of said operating means and acting when extended to determine the printing stroke of said bar, and means oar- 4ried between the type-bar and said links to MARION R. MCCi-arrnnr, JnNNm P. THonNn. 

